Integrated circuits are typically formed on a semiconductor substrate such as a silicon wafer or other semiconducting material. In general, layers of various materials which are either semiconducting, conducting or insulating are utilized to form the integrated circuits. By way of example, the various materials are doped, ion implanted, deposited, etched, grown, etc. using various processes. A continuing goal in semiconductor processing is to reduce the size of individual electronic components thereby enabling smaller and denser integrated circuitry.
One type of circuit device is a capacitor. As capacitors continue to get smaller, there is a continuing challenge to attain sufficient capacitance despite decreasing size. This has been approached both by developing improved materials and in the physical design of the capacitor, for example utilizing stacked and trenched constructions. A capacitor's capacitance is inherently a function of the amount of surface area between the electrodes and the capacitor dielectric region. Rougher surfaces have inherently higher surface areas than do smoother surfaces. Accordingly, increasing the degree of surface roughness of the capacitor electrodes is recognized as one way of facilitating maximum capacitance between an electrode and a capacitor dielectric region. This invention is directed to a method of increasing the surface roughness of certain metals.
While the invention was motivated in addressing the above issues, it is in no way so limited. The invention is only limited by the accompanying claims as literally worded (without interpretative or other limiting reference to the above background art description, remaining portions of the specification or the drawings) and in accordance with the doctrine of equivalents.